Franz lindner



(No Model.)

I. LINDNER. REPEATING MECHANISM FOR PIANOS.

Patented Dec. 4, 1894.

Ul\liTEE STATES FRANZ LINDNER,OF DRESDEN, GERMANY.

REPEATING MECHANISMFOR PIANOS.

SPECIFICATION forming part of Letters Patent No. 530.188, dated December 4, 1894.

Application filed July 3,1894. Serial No. 516,457- (No model.) Patented in Germany September 27, 1892, No. 74,725, and

October 30, 1892,110. 72,928-

To all whom it may concern:

Be it known that, I, FRANZ LINDNER, a subject of the King of Saxony, residing at Dresden, Saxony, have invented certain new and useful Improvements in Repeating Mechanism for Pianos, (for which I have received patents in Germany, dated September 27, 1892, No. 74,725, and October 30, 1892, No. 72,928,) of which the following is a specification.

The present invention relates to repeating mechanism for pianos having vertical wires and generally known as cottage pianos 0r upright pianos.

A repeating mechanism is understood by those skilled in the branch to be a device by means of which the hammer, after having been struck can be brought into position for the second stroke instantaneously, 'i. 8., when it has only accomplished about a quarter of its return fall into the position of rest, so that the hammer, however rapid the repetition, will strike the wire at each depression of the key, with positive certainty.

Repeating devices for horizontal or grand pianos have already been constructed, but hitherto no satisfactory repeating mechanism has been devised for upright pianos.

Generally, a repeating mechanism is supposed to mean aquick return fallof the hammer, without necessarily involving a positively accurate action of the jack in falling under the knuckle before the key has again risen from its depression. Thus with the devices hitherto employed it is easily possible, that the hammer and knuckle may fall onto the jack immediately on the release of the key so that thejack cannot properly get into position under the knuckle until the key has returned to its position of rest. Thus with all the repeating mechanisms hitherto known, shortly after the hammer has struck the Wire it reaches a dead center, which cannot be mathematically determined, and at which point the key cannot operate the hammer. This defect becomes more noticeable, when the pivot of the hammer gets worn, after the instrument has been in use a short time, and it is owing to the same that when trilling or when playing very softly, it often happens that the note does not respond to the touch of the key.

reception of the bumper p.

In the accompanying drawingaside elevatlon of a piano mechanism constructed ac cording to the present invention is shown,

representing the device by means of which the above enumerated defects are avoided.

The device illustrated in the drawing is in connection with a piano mechanism having an upper muffler device, but the invention mayjust as easily be applied to pianos with an under muflier system. In Order to clearly distinguish the novelties comprised in this invention from what is already known, on the drawing, the latter parts are indicated bv means of reference letters While figures are employed to indicate the former.

A is the muffler beam carrying the arms a to which the lever b is pivoted.

c is the mother attached to the lever 19 by means of a strong angle wire. To the free end of the lever b is pivotally attached the lifting arm d. v

Bis the forte lifting bar. The hammerf is in its position of rest with its stem 9 leaning against'the cushion e, the knuckle h being pivotallyattached to a bracket 71 of the hanger K. The bracket or arm Z is also attached to the hanger K. The jack lever m is pivoted to the arm Z and carries at its free end the bridle wire m having bridle n attached to the knuckle h. o is the back check for the The carting or distance between the top of the jack and the knuckle is regulated by an adjusting screw t arranged in the abstract 3. o is the guard and w the pressure batten for regulating the play of the keys.

In order to attain the object in view the following parts are employed in connection with the above mentioned mechanism:an angle lever or fly jack l3, pivoted to the bracket 2 of the hanger K and having a spring l acting against its lower end, said Splingbeing adjustable by means of a screw 5 arranged in the jack standard. The play of the said fly jack 13 is regulated by an adjusting screw 6 penetrating the upper shank of the same and fixed in the hanger K. The upper end of the said fly jack engages under the lower projection 7 of the knuckle h and effectually prevents the hammer from falling back from the string too quickly for the jack top to properly engage under the knuckle. Thus however quickly the note is repeated the jack will always fall into proper position under the knuckle, the movement of the said knuckle being so regulated by the fly jack as to efiectually prevent its falling so quickly as to pass the top of the jack in which case the latter could not get into proper position until the key has returned to its position of rest.

Another improvement comprised in this invention is the arrangement of the jack spring a as also the construction of the same which is three or four times as strong as usually made. This spring is arranged to contact with the toe of the jack at 14-t'. e., at a point as near as possible to the pivot of the said jack, so that the extra power of the spring is to a certain extent neutralized. The advantage of this arrangement is that owing to the said spring being stronger it will not break so easily and secondly the friction of the spring against the jack is very considerably reduced.

Another improvement is the arrangement of the jack on the jack lever m so that the pivot of the said jack shall move in the arc of a circle 9 said are passing the head of the abstracts at a certain distance from the point of contact of the said abstract with the jack lever marked by 8. Thus the jack pivot bears on the jack lever at a point nearer the end of the said jack lever than the point of contact of the latter with the abstract 5 instead of between the latter point and the pivot of the jack lever as hitherto. In order however to attain the standard play or depth of play of the keys with this novel arrangement of the jack pivot, which is eight to ten millimeters, the pivots of the keys must be shifted back from 12 to 13, and thus the front part of the key lengthened. The advantage is that by means of this arrangement the keys attain a length equal to that of the keys of first class grand pianos and can be manipulated with equal elasticity.

I claim as my invention 1. In an upright piano, the combination with the hammer and its stem, of a hanger K, spring fly jack 1, 3, pivoted thereto, and knuckle h having projection 7, such fly jack adjusted to play within the space between said hanger and said projection, substantially as set forth.

2. In an upright piano, the combination with the hammer and its stem, of a hanger K, fly jack 1, 3, flat spring 4 attached to the jack standard and provided with adjusting screw 5, said spring adapted to press against the lower arm of the said fly jack, and knuckle 71. having projection 7, the upper arm of such fly jack adjusted to play within the space between said hanger and said projection, substantially as set forth.

3. In an upright piano, the combination with the hammer, and its stem, of a hanger K, fly jack 1, 3, pivoted thereto, a spring 4 for actuating the same provided with adjusting screw 5, knuckle it having projection 7, the upper arm of the fly jack adjusted to play within the space between said hanger and said projection, and screw 6 for regulating the position of the upper shank of the fly jack, substantially as set forth.

4. In an upright piano, the combination With hangerK,ofaspring flyjack 1,3,knuckle it having projection 7, and regulating screw 6, the upper shank of the fly jack adjusted to play between said. hanger and said projection, substantially as set forth.

5. In an upright piano, the combination with hanger K ofaspring flyjack 1, 3, knuckle h having projection 7, the upper shank of the fly jack adjusted to play between said hanger and said projection, a jack q and a spring a adjusted to bear against the lower end of jack (1 near the pivot of the latter in the manner and for the purposes substantially as set forth.

6. In a piano, the combination with hanger K of a fly jack 1, 3, pivotally connected thereto, knuckle h having projection 7, the upper shank of the flyjack adjusted to play between said hanger and said projection, jack lever 'm, and a jack (1 mounted thereon, the distance between the pivot of the jack lever and its point of contact with the abstract'being less than the distance between said pivot and the pivot of the jack, substantially as and for the purposes specified.

7. In a piano, the combination with the fly jack 1, 3, having spring 4 with adjusting screw 5 and a regulating screw 6 attached to the upper shank of said fly jack, jack q, and a spring 11. hearing against said jack near its pivot the distance between the pivot of the jack lever and its point of contact with the abstract being less than the distance between said pivot and the pivot of thejack, substantially as set forth.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

FRANZ LINDNER.

WVitnesses:

HERNANDO DE SoTo, OSCAR KELLER. 

